Related papers: Conductance quantization in etched Si/SiGe quantum…
Single-electron occupation is an essential component to measurement and manipulation of spin in quantum dots, capabilities that are important for quantum information processing. Si/SiGe is of interest for semiconductor spin qubits, but…
Fractional magnetisation plateaus, in which the magnetisation is pinned at a fraction of its saturated value within a range of external magnetic field, are spectacular macroscopic manifestations of the collective quantum behaviours. One…
Using the mechanically controlled break junction technique at low temperatures and under cryogenic vacuum conditions we have studied atomic contacts of several magnetic (Fe, Co and Ni) and non-magnetic (Pt) metals, which recently were…
The exact expression for the phase-dependent linear conductance of a weakly damped superconducting quantum point contact is obtained. The calculation is performed by summing up the complete perturbative series in the coupling between the…
We study the transport properties of a three dimensional atomic-scale contact in the ballistic regime. The results for the conductance and related transmission eigenvalues show how the properties of the ideal semi-infinite leads (i.e.…
A quantum wire is fabricated on (001)-GaAs at the intersection of two overgrown cleaves. The wire is contacted at each end to n+ GaAs layers via two-dimensional (2D) leads. A sidegate controls the density of the wire revealing conductance…
We report on measurements of the electrical conductivity in both a 2D triangular lattice of metallic beads and in a chain of beads. The voltage/current characteristics are qualitatively similar in both experiments. At low applied current,…
We present the findings of the 0.7(2e2/h) feature in the hole quantum conductance staircase that is caused by silicon one-dimensional channels prepared by the split-gate method inside the p-type silicon quantum well (SQW) on the n-type Si…
We report on the realization and top-gating of a two-dimensional electron system in a nuclear spin free environment using 28Si and 70Ge source material in molecular beam epitaxy. Electron spin decoherence is expected to be minimized in…
We report high-bandwidth charge sensing measurements using a GaAs quantum point contact embedded in a radio frequency impedance matching circuit (rf-QPC). With the rf-QPC biased near pinch-off where it is most sensitive to charge, we…
The past few years have witnessed increased attention to the quest for Majorana-like excitations in the condensed matter community. As a promising candidate in this race, the one-dimensional chiral Majorana edge mode (CMEM) in topological…
We present results of experimental and theoretical investigations of electron transport through stub-shaped waveguides or electron stub tuners (ESTs) in the ballistic regime. Measurements of the conductance G as a function of voltages,…
We obtain the conductance of a system of electrons connected to leads, within time-dependent density-functional theory, using a direct relation between the conductance and the density response function. Corrections to the non-interacting…
We study the electronic transport through a quantum wire (QW) with a strong side coupled quantum dot (QD). We obtain a linear conductance with lateral peaks when the gate voltage, is located near the edge of the conduction band. The…
We study one dimensional clean systems with few channels and strong electron-electron interactions. We find that in several circumstances, even when time reversal symmetry holds, they may lead to two terminal fractional quantized…
We present measurements of quantized conductance in electrostatically induced quantum point contacts in bilayer graphene. The application of a perpendicular magnetic field leads to an intricate pattern of lifted and restored degeneracies…
Kondo effect in the vicinity of a singlet-triplet transition in a vertical quantum dot is considered. This system is shown to map onto a special version of the two-impurity Kondo model. At any value of the control parameter, the system has…
We present the findings for the fractional quantum conductance of holes that is caused by the edge channels in the silicon nanosandwich prepared within frameworks of the Hall geometry. This nanosandwich represents the ultra-narrow p-type…
Zero length quantum wires (or point contacts) exhibit unexplained conductance structure close to 0.7 X 2e^2/h in the absence of an applied magnetic field. We have studied the density- and temperature-dependent conductance of…
Contact resistance is a severe performance bottleneck for electronic devices based on two-dimensional layered (2D) semiconductors, whose contacts are Schottky rather than Ohmic. Although there is general consensus that the injection…